From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id 980209000C2 for ; Wed, 6 Jul 2011 05:31:59 -0400 (EDT) Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp03.in.ibm.com (8.14.4/8.13.1) with ESMTP id p669VloK022319 for ; Wed, 6 Jul 2011 15:01:47 +0530 Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p669VlbL3715080 for ; Wed, 6 Jul 2011 15:01:47 +0530 Received: from d28av02.in.ibm.com (loopback [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p669Vl8g030831 for ; Wed, 6 Jul 2011 19:31:47 +1000 Date: Wed, 6 Jul 2011 15:01:46 +0530 From: Ankita Garg Subject: Re: [PATCH 0/5] mm,debug: VM framework to capture memory reference pattern Message-ID: <20110706093146.GB19518@in.ibm.com> Reply-To: Ankita Garg References: <1309854159-8277-1-git-send-email-ankita@in.ibm.com> <20110706020103.53ed8706.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110706020103.53ed8706.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, svaidy@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, Matt Mackall Hi, On Wed, Jul 06, 2011 at 02:01:03AM -0700, Andrew Morton wrote: > On Tue, 5 Jul 2011 13:52:34 +0530 Ankita Garg wrote: > > > > > This patch series is an instrumentation/debug infrastructure that captures > > the memory reference pattern of applications (workloads). > > Can't the interfaces described in Documentation/vm/pagemap.txt be used > for this? The pagemap interface does not closely track the hardware reference bit of the pages. The 'REFERENCED' flag maintained in /proc/kpageflags only indicates if the page has been referenced since last LRU list enqueue/requeue. So estimating the rate at which a particular page of memory is referenced cannot be obtained. Further, it does not provide information on the amount of kernel memory referenced on behalf of the process. -- Regards, Ankita Garg (ankita@in.ibm.com) Linux Technology Center IBM India Systems & Technology Labs, Bangalore, India -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org